In _The Psychology of Reasoning_[38] M. _Alfred Binet_ makes reasoning a process of the formation of mental images. He finds no decided difference between perception--the cognizance of sensations and assignment of them to their source--and logical reasoning. "The two operations are both reasonings, transitions from the known to the unknown"; "the two extremes of a long series of phenomena." A premise is "a judgment, an association of images," and a conclusion that follows from the premises is "an association of images produced by other associations." The theory of three images--the two premises and the conclusion--"is applicable to reasonings of every kind, and therefore constitutes a general theory of reasoning.... If it be recollected that images are fragments, residues of former sensations; that they spring from the place where former sensations have been received, in the sensory centers of the cerebral surface layers, it will be understood that the purpose of these images in grouping themselves in reasonings, according to the laws of their affinity, is to replace the absent sensations. Such is therefore the function of reasoning; it enlarges the sphere of our sensibility, and extends it to all objects which our senses can not know directly. Thus understood, reasoning is a _supplementary sense_, which has the advantage of being free from those strict conditions of time and space--the two enemies of human knowledge." In memory, "the suggested image is projected and localized in the panorama of the past, of which it appears to be a fragment." Imagination is "a faculty of creating assemblages of images which do not correspond to any external reality." [Footnote 38: The Psychology of Reasoning. Based on Experimental Researches in Hypnotism. By Alfred Binet. Chicago: The Open Court Publishing Company. Pp. 191.]